The overall objective is to identify dietary risk and protective factors for cancer that will lead to the control of this disease. The program takes advantage of the multiethnic, multicultural population of Hawaii which provides unique opportunities for conducting this research. During the current grant period, substantial progress has been made on six projects, each of which is nearing the completion of data collection: surveillance on a prospective cohort; case-control studies of malignant melanoma, colorectal cancer and endometrial cancer; computation of incidence rates by place of birth for four ethnic groups and comparison with corresponding dietary intake patterns; and the development of a telephone diet history interview based on our tested face-to-face method. For the renewal period, we will continue our pursuit of the dietary etiology of cancer. Three projects are described, including: 1) a case- control study of gastric cancer that will investigate the separate and interactive effects of H. pylori infection and several dietary exposures; 2) a genetic epidemiology study which will attempt to distinguish hereditary from environmental (dietary) contributions to the risk of colon cancer; and 3) continued passive surveillance on a population cohort to test the relationship of diet to several less common cancer sites, and to compare findings among different ethnic groups. These studies are interrelated thematically and methodologically, and share several common core resources, including data collection procedures, computer programming, nutritional support and maintenance of a food composition data bank, and biostatistical support. As an integrated program, the research achieves an economy of effort, and fosters collaborations and intellectual interactions among the investigators that advance the research more effectively.